Drinking Water Data & Databases

Drinking Water Links

EPA maintains drinking water data in several databases, including the Safe Drinking Water Information System - Federal Version (SDWIS/FED) and the National Contaminant Occurrence Database (NCOD).

The agency utilizes this information to help manage environmental programs, and provides public access to the data through the Internet. For other water-related databases maintained by EPA see the Office of Water's databases and software page.

List of Drinking Water Databases

Safe Drinking Water Information System - Federal version (SDWIS/FED)
SDWIS/FED is EPA's national regulatory compliance database for the drinking water program. It includes information on the nation's 160,000 public water systems and violations of drinking water regulations.

Unregulated Contaminant Monitoring Rule (UCMR)
EPA uses data generated by the UCMR to evaluate and prioritize contaminants on the Drinking Water Contaminant Candidate List, a list of contaminants EPA is considering for possible new drinking water standards.

National Contaminant Occurrence Database (NCOD)
NCOD was developed to satisfy the statutory requirements set by Congress in the 1996 Safe Drinking Water Act (SDWA) amendments. The purpose of the database is to support the U.S. Environmental Protection Agency's (EPA) decisions related to identifying contaminants for regulation and subsequent regulation development. The NCOD contains occurrence data from both Public Water Systems (PWSs) and other sources (like the U.S. Geological Survey National Water Information System) on physical, chemical, microbial and radiological contaminants for both detections and non-detects.